The Faster You Go The More De-Buffs You Get The Slower You Go The More Buffs You Get,
The "Fastest" will only occur if you are travelling very fast (will run if the player is doing the below). It will also increase the level of debuffs, so weakness 2 instead of weakness 1. Same for the "slowest"
Fastest [Debuff] (effect amplifier 2)
- boating
- horse
- minecart
- elytra
- speed effect 2
Fast [Debuff] (effect amplifier 1)
- sprint
- swim
- fly
- speed 1
Normal [None]
- Standing still
Slow [Buff] (effect amplifier 1)
- walking (normal walking speed)
- pig riding
- falling
Slowest [Buff] (effect amplifier 2)
- crouching
- slowness 2